Electromagnetically-operated sounder.



C. J. SCHWARZE. ELBGTROMAGNBTIGALLYOPERATED SOUNDER. APPLICATION FILED 0013.13. 1910.

L92 l l y@ Patented Mar. 3l, 1914 'Uff/mmm@ QW @QW UNITED sTATEs PATENT oEEIoE.

CARL J. sCHWAazE, or ADRIAN, MICHIGAN, AssIGNon To SCHWARZE ELECTRIC coMrANY, or ADRIAN, MICHIGAN, A roozaroEATIoN or MICHIGAN.

ELECTROMAGNETICALLY-OPERATED SOUNDER.

specification or Letters Patent Application filed October 13', 1910. Serial o. 586,848.

Patented Mar. 31, 1914.

To all whom t may concern:

-Be it known that I, CARL J. SCHWARZE,

a citizen of the United States of America',

residing at Adrian, in the county of Lenawee and State ofMichigau, have invented certain new and useful Improvements` in Electromagnetically-Operated Sounders, of

`which the following is a specification, reference being had phereinto the accompanying drawings.

The invention relates to Sounders or audible alarm devices, and has more particular reference to constructions in which the sound is produced by anelectromagnetically vibrated member. I u

vlt is the object of the Invention toobtam a loud sounding alarm which maybe operv ated by comparatively small battery power,

. the casing adjacent to thecap B and secured at the margin by clamping between.

further to obtain a compact, simple and inexpensive construction,V further to avoid sparking of the make and break electrodes, and still further to'secure 'advantages more fully hereinafter set forth.

lin the drawings','-Figure l is a central longitudinal section through the sounder;l F ig. 2 is a plan view thereof with the cap.`

removed; Fig. 3 is a dlagram illustrating the connection and arrangement of the electric circuits. Fig. 4 is a fragmentary sectional view showing the manner in which the binding posts secure the cap to the .cas1ng. A is a casing preferably of circular form and having at opposite ends thereof the caps Band-C.

D is a metallic diaphragm stretched across flanges E and E2 respectively of the casing A and cap B by bolts F.

G is an ironplate parallel to but spacedl from the diaphragm D by a gasket E and plate of resilient material secured at its` outer'end -to the casing A and bifurcated at lits inner end to embrace the stem K.

N .isa collar on the stem for engagingthe bifurcation of the member M.

O is'a contact mounted on the member M,

and P is an .adjustable contact point mounted on a support Q, and cooperating with the contact 0. R is a spring secured to the cas- Ing A and extendinginto the path of the 'end of the stem K.

The electric connections for the sounder are formed through terminal posts S which also form the mechanical means of securing the `cap C to the casing A but which are v electrically insulated therefrom. As shown in Fig. et, the posts S extend through the v Cap C and engage lugs S extending inward in the upper end of. the casing. v The binding post S is insulated from the cap C by insulation S2 and from the casing A by insulation S3. From these terminals, connection is `made through conductor T to the contactv P, `While the opposite terminal is connected by-a conductor T ,to the coils l from which the circuit leads to the contact '0 on the vibrator M. Thus when the circuit is closed the magnets willy be energized attract- Ingthe disk armature L and causing the stem K to deliver a blowagainst 'the diaphra D. This movement 'will cause the collar N to dex the member M withdrawing the Contact O from the coperating contact ,P and openingthe circuit which by denergizing the magnet, ermits the stem K and armature L to .be t rown backward by the recoil of the .diaphragm D. In this return movement, the stem is moved into Contact with the spring R which formsia yieldable bu'er overcoming the inertia of the moving parts.

The ra id opening and closing of the electric circuit of almagnet will cause the generation of a spark at thelseparated electrodes. This ll have avoided to a large extent by providing each of 'the magnet cores with an additional coil `U which is short circuited and serves to discharge the induced current which otherwise would pass through the spark cap. Spark difficulties: are still further guarded against by the vuse of'` a condenser having the opposite inductors thereof connected respectively Withthe contacts O and P. This condenser I preferably constructin cylindrical form and preferabl 'by adjacent insulated wires V and V Whic 1 ed to the armature and stem, causing the latter to strike against the diaphragm D- and thereby generate the sound. The resiliency of the diaphragm will causethe recoil of the thereto and centrally thereof,l a bearing instem and armature, and the amplitude of the vibratory movement will vary in accordance to variations in speed. Thus in starting, the armature' may only `move far enough in its return movement to cause the closing of the electric circuit through the contacts O 'and P, but when full speed is acquired (which is almo-st instantaneous) the inertia of the moving parts will further deflect the spring R, increasing the amplit-ude of vibration.

For intensifying the sound, the cap B is preferably formed. with a nipple X which may be attachedto a horn or megaphone.

What I claim as my invention is l. The combination with a casing, of a diaphragm extending thereacross, a reciprocatory rod adapted to impinge againstv said diaphragm and extending perpendicular which said rod is slidably secured, a disk armature on said rod, and an electromagnet having a plurality of poles concentric with the axis of said rod and exerting a balanced pull on said armature in a direction toward said diaphragm, a spring for retract-ing said rod, a make and break circuit closer actuated by said rod and controlling said magnet, and a buifer spring at the opposite end of said rod.

2. The combination with a casing, of a diaphragm extending thereacross, an electromagnet arranged within said casing and having a plurality of poles concentric withv the axis thereof, a bearing in the center of said casing, a reciprocatory rod slidably secured in said bearing and adapted to impinge against said'diaphra m, a disk armature mounted on said r a spring for retract-ing said rod, a make and break circuit closer coperating with said spring and conr the opmembers being a disk sound producer and the initialmovement of said 'reciprocatory member being independent of both of said resilient members.

4. The combination with aresilient disk sound producer of a resilient buffer, a reciprocatory member movable therebetween and havin its movement in one direction yieldably-limited by said vsound-.producer and its movement in the opposite direction yieldably limited by said resilient buffer, and electro-magnetic means for initially impinging said' reeiprocatory member `against saidresilient sound producer, the initial movement of said reciprocatory member being independent of said resilient buffer. 5. The combination with a resilient diaphragm,'of a resilient buffer opposed thereto, a striker substantially freely movable therebetween having its movement in one di-I rection yieldably limited by said resilient diaphragm and its movement in the opposite vdirection yieldably limited by said resilient bulfer, an armature in operative relation to said striker, an electro-magnet for controlling said armature to initially impinge said striker against said resilient sound producer, and a relatively. light spring for holding said armature in normal positlon, the initial movement of said striker being independent of said buffer.

In testi-mon whereof I affix my signature in presence o two witnesses.

CARL J. SCHWARZE. Witnesses:

F. E. Hoo1i, PETER C. Rack. 

